Calculator

Effective Rate and Overrun Estimator

Estimate effective hourly rates and forecast professional services overruns using simple inputs.

Educational only. Validate with your SOW, rate card, and invoice evidence.

Processed in-browser. Nothing is stored.

Inputs

Required

Optional

Formatting only

Defaults to today

$

Required

$

Defaults to 0

$

Required

$

Required

Required

$

Defaults to 0

Optional forecast input

Assumptions

  • Effective rate is computed from current invoice labor amount divided by labor hours.
  • Forecast assumes remaining hours are billed at the current effective rate.
  • Verify budget and change order totals against the SOW and approvals.

Optional context for the memo

Fix validation errors to calculate.

Results

Enter inputs and click Generate.

How to use

  1. Enter the budget NTE, approved change orders, and billed-to-date total.
  2. Add the latest invoice labor amount, hours, and expenses to compute the effective rate.
  3. Include remaining work hours if you want a forecasted overrun.
  4. Generate the memo and share it before the next invoice cycle.

What results mean

Effective hourly rate is labor amount divided by labor hours on the current invoice.

Budget remaining compares total budget against billed-to-date spend.

Projected overrun or headroom uses your remaining hours estimate and chosen labor rate to forecast the final total.

Common pitfalls

  • Using inconsistent labor hour tracking across invoices or time periods.
  • Leaving out pass-through expenses that still hit the budget.
  • Skipping forecast updates as the remaining work estimate changes.

Definitions

Effective rate: Labor amount divided by labor hours.

Overrun: Forecasted total cost above budget.

Budget remaining: Budget minus billed-to-date total.

Change log

v1.0 (2026-01): Latest release